1. Field of the Invention
The present invention relates to carpenters tools and more particularly to a combination level, extensible straight edge and protractor.
2. Description of the Prior Art.
Prior patents generally disclose extensible rules in which one member slidably overlies another member for longitudinal movement of one member with respect to the other in which indicia, on the respective members, indicate the combined measurement. Some extensible rules have lateral projections in which the respective member forms a caliper-like device for measuring external dimensions while other patents disclose an arcuate lateral sector in which one of the members is hinged to the other for disposing the members to define a selected angle.
This invention is distinctive over prior patents by providing a pair of members longitudinally slidable relative to each other which are maintained in a sliding relation by a thumb screw bolt extending through one member and slidable in a slot in the other member wherein guide pins maintain the members in aligned relation and a circular groove, at one end of the slot containing member, permits selected angular positioning of the two members to form a protractor.